The use of polymeric materials in hair care products is of increasing importance. In the hair care area, polymers can be used for hair hold and setting products, for hair conditioning products, and in shampoos. For example, rinse-off hair care conditioning/styling products typically comprise a hydrophobic polymer which remains after rinsing the hair. The polymer is solubilized in a suitable solvent which evaporates to leave the polymer treated hair. The solvent must be one in which the polymer is substantially soluble (i.e., the solvent is generally hydrophobic).
A hair styling polymer should provide certain styling benefits. For example, the styling polymer should not leave the hair feeling and looking coated. Also, the styling polymer should have sufficient adhesion without being unduly brittle such that the hair can be restyled, e.g., with heated implements, and then maintain the new style. Still in addition, the styling polymer should be deliverable from a shampoo matrix, i.e., they should deposit on the hair during the washing process and remain behind on the hair fibers. Therefore, in the hair styling area, it is desirable to provide polymers which provide improved styling benefits and which can be delivered from a wide variety of matrices, including rinses, leave-on compositions, and shampoos. It is also desirable to provide hair styling compositions which have improved hair feel performance (after application and drying of such compositions) at a particular level of hair styling or conversely, improved hair styling for a particular level of hair feel performance.
Hair styling compositions have included copolymers of hydrophobic monomers. See, e.g., EPA 92913354.4, published May 23, 1994. While such compositions provide certain hair care benefits, there remains the need for alternative hair care polymers having improved hair styling benefits and adhesive properties.
The formulation of an improved hair styling composition presents particular challenges. Not only must the polymer be capable of providing the desired styling benefits including adhesive properties, it must be formulated such that these properties are readily delivered to the hair. Thus the polymer must be suitably solubilized in the composition.
The linear copolymers of the present invention are hydrophobic materials derived from certain monomers which provide certain solubility and thermomechanical properties, more particularly desired properties of defined solvent solubility, low water solubility, and high Tg. These characteristics make these copolymers highly useful for formulation in hair care products. For example, the polymers of the present invention tend to have improved hair styling benefits (low tendency to clump, make hair look dirty or impart hair stickiness) and good adhesive properties without unacceptable brittleness such that the hair styling benefits are maintained.
It is an object of the present invention to provide hair care compositions containing certain hydrophobic linear copolymers.
It is another object of the present invention to provide hair care compositions having improved style and hold benefits.
It is another object of the present invention to provide novel hair care compositions having improved conditioning benefits.
It is a further object to provide hair care compositions that provide good hair styling benefits (e.g., having a low tendency to clump, make hair look dirty or impart hair stickiness, and good adhesive properties without unacceptable brittleness such that the hair styling benefits are maintained).
These and other objects will become readily apparent from the detailed description which follows.